Myelodysplastic syndromes

Myelodysplastic Syndromes at a Glance

• Myelodysplastic syndromes (MDS) are a group of diseases in which the bone marrow does not make enough healthy blood cells.
• MDS is more common in men and whites.
• Other risk factors for myelodysplastic syndromes include being older than 60 years; past treatment with chemotherapy or radiation therapy; exposure to certain chemicals, including tobacco smoke, pesticides, and solvents such as benzene; and exposure to heavy metals, such as mercury or lead
• Symptoms of myelodysplastic syndrome include shortness of breath, weakness or feeling tired, having skin that is paler than usual, easy bruising or bleeding, petechiae (flat, pinpoint spots under the skin caused by bleeding), fever or frequent infections.

About MDS

The MDS are diagnosed in slightly more than 10,000 people in the United States yearly for an annual age-adjusted incidence of 3.4/100,000 people. The MDS are more common in men and whites.

Myelodysplastic syndromes are diseases of the blood and bone marrow. Normally, the bone marrow makes blood stem cells (immature cells) that develop into mature blood cells over time. A blood stem cell may become a myeloid stem cell or a lymphoid stem cell. The lymphoid stem cell develops into a white blood cell. The myeloid stem cell develops into one of three types of mature blood cells; red blood cells, infection fighting white blood cells or platelets.

In myelodysplastic syndromes, the blood stem cells do not mature into healthy red blood cells, white blood cells, or platelets. The immature blood cells, called blasts, do not function normally and either die in the bone marrow or soon after they enter the blood. This leaves less room for healthy white blood cells, red blood cells, and platelets to develop in the bone marrow. When there are fewer blood cells, infection, anemia, or easy bleeding may occur.

Types of Myelodysplastic Syndromes

• Refractory anemia.
• Refractory anemia with ringed sideroblasts.
• Refractory anemia with excess blasts.
• Refractory anemia with excess blasts in transformation.
• Refractory cytopenia with multilineage dysplasia.
• Myelodysplastic syndrome associated with an isolated del (5q) chromosome abnormality.
• Unclassifiable myelodysplastic syndrome.

Risk Factors

Risk factors for myelodysplastic syndromes include the following:

• Being male or white.
• Being older than 60 years.
• Past treatment with chemotherapy or radiation therapy.
• Being exposed to certain chemicals, including tobacco smoke, pesticides, and solvents such as benzene.
• Being exposed to heavy metals, such as mercury or lead

Symptoms

Possible signs of myelodysplastic syndrome include:

• Shortness of breath.
• Weakness or feeling tired.
• Having skin that is paler than usual.
• Easy bruising or bleeding.
• Petechiae (flat, pinpoint spots under the skin caused by bleeding).
• Fever or frequent infections.